Window-sash balance.



W. E. FORSYTH & E. E. WHITMORE.

WINDOW SASH BALANCE.

APPLICATION FILED JAN. 5, 1912.

Patented Nov. 18, 1913.

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rrn MAW-NT @FlfCE-l WILLIAM H. ronsY'r'rr AND EDWARD n. WHrrr/roan, or CHIC-AGO, IL'LrN'oIs, Assrem ons To 'CURTAIN sUr'rLY COMPANY, or orrroeeo, intl-nots, A CORPORATION or 'NEW Varrasar.

WINDOW-ssen BALANCE.

ances, and has particular reference to sash balances of the type wherein a coiled torsion `spring is opposed to the weight of the'sash.

While our improved balance has particular utility in connection with the sashesoil car windows and the like and will be described in such lconnection the invention is not limited thereto.

Sash balancesV of this kind are rotatably mounted horizontally in the frames of windows above the sashes to be raised and lowered, and have chains or cables connecting the Windows with the spring-actuated roller of the device. Hitherto such rollers have beenmadfe in most cases of tin, in some instances eiorts being made to reinforce and strengthen the same; but owing to the weight of the sashes and the jarring of the trains, the chains or cables frequently cut or indent the rollers ina very short time so that they must be replaced. These tin rollers have been given an excessive diameter, not only for purposes of strength but also to provide sullicient clearance for the coiled spring within, a portion of the interior of the roller being occupied by an undercut longitudinal groove or indent-ation of the tin, such groove being formed for the reception of holding means for the window supporting chains. As the space for rollers of this kind in car Windows is very limited the excessive diameter of the rollers heretofore in use yhas been very objectionable, especially where it is desired to use two such rollers, the necessity in such case requiring them to be placed one above the other, with many obvious ,disadvantages in application, service and repair. Heretofore, too, rollers of this type have been made usually of standard or' specified length, and as it fre quently happens that the Window measurements do not correspond with those of the `sash bala-nce, difficulties have arisen in that regard. Other troubles have been vexperispecifmation off Letters Patent.

Application filed January b, 1912. Serial No. 669,664.

Patented Nov. is, i913.

ence'd inhthat various parts of the heretofore-suggested and used constructions are rigidly connected together, requiring muti-` lation, Vor dismemberment thereof when replacement becomes necessary. A particular disadvantage in this regard has been that the internal coil spring 'and it-s connected parts have not been removable vfrom Vthe roller without some physical changing ofthe retaining parts, such as bending or breaking` the same. Up to the present time the end mem-bers and the internal block'have been securedl in their respective positions by` crimping upon them a portion of the tube. Such crimping not Vonly does not permit the parts vto be separated or reassembled by the repair'man, but these members 4are inclined to work loose in service.

Hitherto the chains or cables used in sash balances of this kind have usually been rigidly secured to the periphery of the roller either by riveting or by means of a block held within the roller groove hereinabove referred to. to install, remove or repair Sashes and sash balances, it being necessary that the two members be handled together.

It is the object'of the present invention Vto overcome the disadvantages hereinabove mentioned, and this is accomplished by the provision of a sash balance constructed of metallic tubing of comparatively small diameter but of substantial thickness, having window-holding chains or cables detachably secured thereon, the roller being provided with an adjustable end member and easily removable end and spring members, the in vention comprising various other features of improvement, as will be hereinafter pointed out and claimed.

' These improvements and advantages will be more readily understood by reference to the accompanyingdrawings, forming a part of this specification, which illustrate a prefVV is an elevation of the keyor spear end of the sash balance; Fig.V 4L iS a transverse vertical section on the line 4-21 pfFig. 2; Fig. V5 is a transverse vertical section on the line tlg-5 This has made it diilicult at times of Fig. 2, and Fig. 6 is a sectional and plan view of the end member or fastener for the sash-supporting chains.

The outer tube or hollow roller 10 of the sash bal anceshown in the drawings is preferably made of seamless or brazed steel tubing i of substantial thickness so that Vit may resist strains which are at times severe. At one end of the tube isthe spindle end member 11 having the usual pintle 12 formed to rotate in a bearing in a supporting member (not shown). The barrel portion 13 of the end member 11 fits within the end of the tube 10. The annular flange 14 on this end member limits the inward movement thereof, coacts with the bolt 15 in providing rigidity between said end member and the outer tube 10, and has also the function of preventing the chain or cable from traveling oif the roller. rlhe bolt 15 passes diametrically through the outer tube and the barrel portion of said end member, the bolt being provided with a head 1G and nut 17. A locking `washer 18 of ordinary construction prevents the nut from working loose. Each end of the bolt 15 lpasses through a longitudinal slot 19 in the tube 10, by which arrangement it is apparent that the end member 11 may be partially withdrawn from the tube 10, thereby lengthening the sash balance between its bearing members, the tightening of the bolt 15 holding the parts in closed or extended position.

The shaft-bearing end member 2O is provided with a barrel portion 21 and flange 22, which parts serve the same functions respectively as those of the end member 11. This member 20 is secured against rotation relative to and withdrawal from the tube 10 by a pair of oppositely disposed screws 23 (only one of which is shown) passing through suitable openings in the tube 10 and threaded into the member 20, a locking washer 23a being preferably used to prevent accidental unscrewing. By removing these screws and the bolt 25 the end member 20 and its connected parts may be readily withdrawn from the tube or casing 10.

Tithin the roller or tube l() is a block 24 rigidly secured to the roller by a throughbolt 25 identical with the bolt 15. An annular flange 26 on the block 24 provides a bearing recess for the shaft or mandrel 27, the latter consisting preferably of metal tubing, and the block being rotatable upon the end thereof. The other end of the hollow mandrel 27 is attached to the shank 28 of the spear or key end 29 by means of the rivet which is formed to receive a pawl 32 pivoted to the end member 20, this groove and pawl being adapted to lock the outer and inner mechanisms ofthe sash balance together in the usual manner.

The shank 28 passes through an axial aperture 20a in the end member 20, said end member being carried by and adapted to rotate upon said shank, it being understood that the key or spear end is fixedly held against rotation by its engagement with Va rectangular socket in a supporting member (not shown). A coil or torsion spring 32 loosely surrounds the shaft 27, one end 33 of which spring passes through a longitudinal aperture 34 in the block 24 and is bent to prevent the withdrawal thereof and also to keep the block in assembled relation to the'spring andvmandrel when the interior mechanism is removed from within the tube. The other end 35 of the spring 32 passes through an aperture 36 in the shaft 27 and a registering slot 36 in the shank 28, 'and is bent to prevent withdrawal and to insure the transmission ofpower to and from said spring. Y

An important feature of this invention will now be described, namely, the detachable chains or cables connecting the sliding sash with the sash balance. In the drawings this element is shown as a chain 37, there being preferably two such chains to each sash balance. The lower ends of the chains (not shown) are attached to the sliding sash of the window, and the upper ends thereof are secured on the periphery of the roller 10. Our invention comprises readily attachable chains or cables and so secured to the tube or roller that they may he easily and quickly detached without breaking or bendingthe connecting parts and without removing the roller from the window frame for either such purpose. In the drawings is illustrated a form of conncction for these chains consisting of a slot 38, preferably of rightangular shape, in the wall of the tube 10, the lateral end of the slotbeing enlarged, as at 39, and an end member having a head 40, stem 41 and a reduced stem 42. A. link of the chain 37 having an aperture equal to the diameter of the reduced stem 42 is riveted on said reduced stem, thus leaving a space somewhat greater than the thickness of the wall of the tubing between said head and said link, a washer 43 being preferably employed at the riveting end as shown. The aperture 39 is of such diameter that the head 40 may easily pass therethrough, the other portion of the slot 38 being of restricted width to prevent withdrawal of the fastener head. It will thus be seen that the chains 37 may be readily aiiiXed to and removed from the roller 10.

When the sash is pushed upwardly the action is assisted by the coiled spring 32 which is under torsion. The spear or key end 29 and the hollow mandrel 27 being held stationary while the outer tube and block 24 rotate, the spring 32 -is partially uncoiled and the torsion of the spring 32 is gradually decreased, the chains 37 winding about the roller l0. When the sash is lowered the chains are, of course, unwound and the spring 32 is again placed under increased. torsion.

It will now be readily understood how the numerous disadvantages of the old form of structure are overcome by the present invention, the roller being of comparatively small diameter, strong and durable in construction, and having certain of the parts easily removable and adjustable for the accomplishment of the important functions pointed out. It Will be understood, too, that, if found to be desirable or convenient, the spear or key end may be securely retained in a rectangular opening in its socket-piece instead of in the open rectangular slot as at present used, the adjustment of the end member ll and the removal of the chains 37 permitting the roller to be entirely removed from the window.

lt will be apparent to those skilled in the art that many changes could be made in the detailed construction of the parts herein illustrated and described without departing from the spirit or scope of our invention.

We claim:

l. In a sash-balance, the combination of a hollow slotted metallic roller, an endmember having a barrel portion fitting within an end of said roller, said end-member having an opening registering with said slot, and a bolt in said opening and slot, whereby said end-member is removably and longitudinally adjustably secured to said tube, substantially as described.

Q. In a sash-balance, the combination of a metallic roller having an angular slot therein, and a chain having an end detachably fastened in said slot, substantially as described.

3. In a sash-balance, the combination of a hollow metallic roller having an angular key-hole slot in the wall thereof, and a chain having an end-member, said endmember engaging said slot with a portion of the member inside the roller, substantially as described.

t. in a sash-balance, the combination of a hollow metallic roller having an angular slot through the wall thereof, said slot having enlarged and restricted portions, and a chain having an undercut end adapted other peripherally thereof, said slot havingV an enlarged portion at the terminus of the longitudinal portion, a chain, and an end- Vmember thereon, said end-member comprising a stem and a head, said head being adapted to enter the enlarged portion of said slot and to fasten said chain to said roller by engagement with the inner surface of said tube adjacent to the smaller portion of said slot, substantially as described.

6. In a sash-balance, the combination of a hollow metallic roller, a block detachably secured inside of said roller, a mandrel, Va spear fastened to said mandrel, a roller endmember detachably secured to said roller and rotatably mounted on said spear, means to hold said end-member on said spear, and

means to hold said block to said spring and mandrel, substantially as described. 7. ln a sash-balance, the combination of a hollow metallic roller, and a unitary structure detachably secured in said roller, said structure comprising in combination a block, a mandrel, a spear, a roller end-member, and a spring associated with said block and spear tending to rotate them relatively to one another, substantially as described.

8. In a sash-balance, the combination of a hollow metallic roller having a detachable chain, and a unitary structure comprising in combination a roller end member, a shaft within said roller, a key-end attached to said shaft and projecting through an aperture in one of said end members, a block bolted within said tube and having a bearing rotatable upon said shaft, a spring coiled on said mandrel and fastened at one end thereof to said block and atthe other end thereof to said key-end, substantially as described. Y

l/VILLIAM H. FORSYTI-l. EDWARD E. WHITMORE.

Witnesses WALTER M. FULLER,

LUTHER JOHNS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

